Non-woven fabrics are used in sanitary goods such as disposable diapers and sanitary napkins, packaging materials for consumer and industrial products, and protective clothing. They are usually made from fibers of polyethylene, polypropylene, polyester, or polyamide. Non-woven fabrics made of these fibers are chemically stable under ordinary environmental conditions and, therefore, are usually disposed of by incineration or utilized as landfill. In Japan, incineration is expensive and, with regard to landfill, the chemically stable non-woven fabrics remain intact for long periods of time.
There is a demand for non-woven fabrics, which naturally decompose in a short period of time. This demand cannot be met with conventional biodegradable fibers such as cellulose and protein fibers, which are generally too expensive to be used as disposable non-woven fabrics, and cannot be made into non-woven fabrics by the thermal bond process because they are not thermoplastic. There are biodegradable, thermoplastic resins, but, again, they are generally too expensive for use in disposable non-woven fabrics, or they are not suitable for such applications.